677
FZUS51 KBOX 210505
CWFBOX
COASTAL WATERS FORECAST FOR MASSACHUSETTS AND RHODE ISLAND
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
105 AM EDT TUE APR 21 2026
COASTAL WATERS FROM THE MERRIMACK RIVER MA TO WATCH HILL RI OUT
TO 60 NM
ANZ200-211800-
105 AM EDT TUE APR 21 2026
SYNOPSIS FOR MASSACHUSETTS AND RHODE ISLAND COASTAL WATERS
HIGH PRES BUILDS OVER THE WATERS EARLY THIS WEEK SUPPORTING
RELATIVELY CALM CONDITIONS WITH SEAS LESS THAN 4 FEET AND WINDS
GENERALLY 10 KNOTS OR LESS SUSTAINED. WEAK LOW PRES MAY PASS OVER
THE WATERS WED INTO THU BRINGING SCATTERED SHOWERS.
ANZ250-211800-
COASTAL WATERS EAST OF IPSWICH BAY AND THE STELLWAGEN BANK
NATIONAL MARINE SANCTUARY-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS AROUND 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 4 FT. WAVE DETAIL: NW 3 FT AT 4 SECONDS AND E 2 FT AT
8 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING E
5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N 3 FT
AT 5 SECONDS AND E 2 FT AT 8 SECONDS.
TUE NIGHT
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS
2 TO 3 FT. WAVE DETAIL: E 2 FT AT 6 SECONDS AND NW 1 FOOT AT
3 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS 2 TO 3 FT. WAVE DETAIL: SW 2 FT AT 4 SECONDS AND NE 1 FOOT
AT 5 SECONDS.
WED NIGHT
S WINDS 10 TO 15 KT, DIMINISHING TO 5 TO 10 KT AFTER
MIDNIGHT. SEAS 2 TO 3 FT. WAVE DETAIL: E 2 FT AT 4 SECONDS AND SW
2 FT AT 4 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE
DETAIL: SW 2 FT AT 4 SECONDS AND E 2 FT AT 8 SECONDS.
FRI THROUGH SAT NIGHT
S WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ251-211800-
MASSACHUSETTS BAY AND IPSWICH BAY-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS AROUND 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: N 3 FT AT 4 SECONDS AND E 2 FT AT
8 SECONDS.
TUE
N WINDS 10 TO 15 KT, BECOMING E 5 TO 10 KT IN THE
AFTERNOON. SEAS 2 TO 3 FT. WAVE DETAIL: N 3 FT AT 5 SECONDS AND E
2 FT AT 8 SECONDS.
TUE NIGHT
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS
AROUND 2 FT. WAVE DETAIL: NE 2 FT AT 5 SECONDS AND SE 2 FT AT
5 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS AROUND 2 FT. WAVE DETAIL: SW 2 FT AT 4 SECONDS AND NE 1 FOOT
AT 5 SECONDS.
WED NIGHT
S WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL: S
2 FT AT 4 SECONDS AND E 1 FOOT AT 4 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE
DETAIL: E 2 FT AT 8 SECONDS AND SW 1 FOOT AT 3 SECONDS.
FRI THROUGH SAT
NE WINDS 5 TO 10 KT. SEAS AROUND 2 FT.
SAT NIGHT
S WINDS 5 TO 10 KT. SEAS AROUND 2 FT. A CHANCE OF
SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ231-211800-
CAPE COD BAY-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: N 2 FT AT 3 SECONDS AND SE 1 FOOT
AT 7 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING NE
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT. WAVE DETAIL: N
2 FT AT 4 SECONDS AND SE 1 FOOT AT 7 SECONDS.
TUE NIGHT
S WINDS 5 TO 10 KT. SEAS AROUND 2 FT IN THE EVENING,
THEN 1 FOOT OR LESS. WAVE DETAIL: N 2 FT AT 5 SECONDS AND S
1 FOOT AT 5 SECONDS, BECOMING S 1 FOOT AT 2 SECONDS AND N 1 FOOT
AT 5 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS AROUND 2 FT. WAVE DETAIL: S 1 FOOT AT 2 SECONDS AND N 1 FOOT
AT 4 SECONDS. A CHANCE OF SHOWERS IN THE MORNING.
WED NIGHT
S WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL:
SW 1 FOOT AT 3 SECONDS AND NE 1 FOOT AT 4 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE
DETAIL: W 1 FOOT AT 3 SECONDS AND SE 1 FOOT AT 4 SECONDS.
FRI THROUGH SAT
NE WINDS 5 TO 10 KT. SEAS AROUND 2 FT.
SAT NIGHT
SE WINDS AROUND 5 KT. SEAS AROUND 2 FT. A CHANCE OF
SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ254-211800-
COASTAL WATERS FROM PROVINCETOWN MA TO CHATHAM MA TO NANTUCKET MA
OUT 20 NM-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: N 2 FT AT 5 SECONDS AND E 2 FT AT
8 SECONDS. A SLIGHT CHANCE OF RAIN.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING NE
5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N 3 FT
AT 4 SECONDS AND E 2 FT AT 8 SECONDS.
TUE NIGHT
SE WINDS 5 TO 10 KT, BECOMING SW AFTER MIDNIGHT.
SEAS 2 TO 3 FT. WAVE DETAIL: N 2 FT AT 5 SECONDS AND E 2 FT AT
8 SECONDS.
WED
S WINDS 5 TO 10 KT, INCREASING TO 10 TO 15 KT WITH GUSTS
UP TO 20 KT IN THE AFTERNOON. SEAS 2 TO 3 FT. WAVE DETAIL: S 2 FT
AT 4 SECONDS AND E 2 FT AT 6 SECONDS.
WED NIGHT
SE WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE DETAIL: S
2 FT AT 4 SECONDS AND E 2 FT AT 9 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: SE 2 FT AT 7 SECONDS AND W 1 FOOT AT 4 SECONDS.
FRI THROUGH SAT NIGHT
E WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ255-211800-
COASTAL WATERS EXTENDING OUT TO 25 NM SOUTH OF MARTHAS VINEYARD
AND NANTUCKET-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 15 TO 20 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: NW 2 FT AT 4 SECONDS AND E 2 FT AT 8 SECONDS. A SLIGHT
CHANCE OF RAIN.
TUE
NE WINDS 15 TO 20 KT, DIMINISHING TO 10 TO 15 KT IN THE
AFTERNOON. SEAS 2 TO 3 FT. WAVE DETAIL: N 3 FT AT 4 SECONDS AND
SW 1 FOOT AT 6 SECONDS.
TUE NIGHT
S WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL:
NW 1 FOOT AT 3 SECONDS AND NE 1 FOOT AT 5 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS 2 TO 4 FT. WAVE DETAIL: SW 3 FT AT 4 SECONDS AND NE 1 FOOT
AT 5 SECONDS. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 10 TO 15 KT, BECOMING E 5 TO 10 KT AFTER
MIDNIGHT. SEAS 3 TO 4 FT. WAVE DETAIL: SW 3 FT AT 5 SECONDS AND E
2 FT AT 9 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 2 TO 4 FT. WAVE
DETAIL: SW 3 FT AT 7 SECONDS AND E 2 FT AT 9 SECONDS.
FRI THROUGH SAT
NE WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
SAT NIGHT
E WINDS AROUND 10 KT. SEAS 2 TO 3 FT. A CHANCE OF
SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ256-211800-
COASTAL WATERS FROM MONTAUK NY TO MARTHAS VINEYARD EXTENDING OUT
TO 20 NM SOUTH OF BLOCK ISLAND-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 15 TO 20 KT. SEAS AROUND 3 FT. WAVE
DETAIL: N 3 FT AT 4 SECONDS AND S 1 FOOT AT 6 SECONDS. A SLIGHT
CHANCE OF RAIN.
TUE
N WINDS 15 TO 20 KT, BECOMING W 5 TO 10 KT IN THE
AFTERNOON. SEAS 2 TO 3 FT. WAVE DETAIL: N 3 FT AT 4 SECONDS AND S
1 FOOT AT 6 SECONDS.
TUE NIGHT
S WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL: W
2 FT AT 4 SECONDS AND E 1 FOOT AT 4 SECONDS.
WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS 2 TO
4 FT. WAVE DETAIL: SW 3 FT AT 4 SECONDS AND E 1 FOOT AT
4 SECONDS. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING E AFTER MIDNIGHT. SEAS
3 TO 4 FT. WAVE DETAIL: SW 3 FT AT 6 SECONDS AND E 2 FT AT
9 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 2 TO 4 FT. WAVE
DETAIL: SW 3 FT AT 7 SECONDS AND NW 2 FT AT 3 SECONDS.
FRI AND FRI NIGHT
W WINDS 10 TO 15 KT, BECOMING SE 5 TO 10 KT.
SEAS 2 TO 3 FT.
SAT AND SAT NIGHT
E WINDS 10 TO 15 KT. SEAS 2 TO 3 FT. A
CHANCE OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ232-211800-
NANTUCKET SOUND-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: NW 2 FT AT 3 SECONDS AND S 1 FOOT
AT 6 SECONDS. A SLIGHT CHANCE OF RAIN.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING NE
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT. WAVE DETAIL: N
2 FT AT 4 SECONDS AND S 1 FOOT AT 6 SECONDS.
TUE NIGHT
S WINDS 5 TO 10 KT. SEAS AROUND 2 FT IN THE EVENING,
THEN 1 FOOT OR LESS. WAVE DETAIL: NW 1 FOOT AT 4 SECONDS AND E
1 FOOT AT 4 SECONDS, BECOMING SW 1 FOOT AT 3 SECONDS AND E 1 FOOT
AT 5 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS AROUND 2 FT. WAVE DETAIL: SW 2 FT AT 4 SECONDS AND E 1 FOOT
AT 5 SECONDS. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL:
SE 2 FT AT 4 SECONDS AND W 1 FOOT AT 5 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE
DETAIL: NW 1 FOOT AT 3 SECONDS AND E 1 FOOT AT 4 SECONDS.
FRI THROUGH SAT
NE WINDS 5 TO 10 KT. SEAS AROUND 2 FT.
SAT NIGHT
E WINDS 5 TO 10 KT. SEAS AROUND 2 FT. A CHANCE OF
SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ233-211800-
VINEYARD SOUND-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS AROUND 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: N 2 FT AT 3 SECONDS AND W 1 FOOT
AT 3 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING SW
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT IN THE MORNING,
THEN 1 FOOT OR LESS. WAVE DETAIL: NE 2 FT AT 3 SECONDS AND NW
2 FT AT 3 SECONDS, BECOMING NW 1 FOOT AT 2 SECONDS AND NE 1 FOOT
AT 3 SECONDS.
TUE NIGHT
S WINDS 5 TO 10 KT. SEAS 1 FOOT OR LESS, THEN AROUND
2 FT AFTER MIDNIGHT. WAVE DETAIL: E 1 FOOT AT 3 SECONDS AND SW
1 FOOT AT 4 SECONDS.
WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS AROUND
2 FT. WAVE DETAIL: SW 2 FT AT 4 SECONDS AND E 1 FOOT AT
5 SECONDS. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING E AFTER MIDNIGHT. SEAS
AROUND 2 FT. WAVE DETAIL: SE 2 FT AT 6 SECONDS AND SW 1 FOOT AT
3 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE
DETAIL: SW 2 FT AT 7 SECONDS AND NW 1 FOOT AT 3 SECONDS.
FRI AND FRI NIGHT
NW WINDS 5 TO 10 KT, BECOMING S. SEAS AROUND
2 FT, THEN 1 FOOT OR LESS.
SAT AND SAT NIGHT
E WINDS 5 TO 10 KT. SEAS 1 FOOT OR LESS. A
CHANCE OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ234-211800-
BUZZARDS BAY-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: N 1 FOOT AT 3 SECONDS AND SW
1 FOOT AT 5 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING S
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT IN THE MORNING,
THEN 1 FOOT OR LESS. WAVE DETAIL: NW 2 FT AT 4 SECONDS AND NE
1 FOOT AT 3 SECONDS, BECOMING NE 1 FOOT AT 3 SECONDS AND W 1 FOOT
AT 3 SECONDS.
TUE NIGHT
S WINDS AROUND 10 KT. SEAS 1 FOOT OR LESS. WAVE
DETAIL: NE 1 FOOT AT 3 SECONDS AND SW 1 FOOT AT 4 SECONDS.
WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS AROUND
2 FT. WAVE DETAIL: SW 2 FT AT 4 SECONDS AND E 1 FOOT AT
5 SECONDS. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING E AFTER MIDNIGHT. SEAS
AROUND 2 FT. WAVE DETAIL: SE 2 FT AT 6 SECONDS AND W 1 FOOT AT
3 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE
DETAIL: SW 2 FT AT 7 SECONDS AND E 2 FT AT 9 SECONDS.
FRI AND FRI NIGHT
N WINDS 5 TO 10 KT, BECOMING S. SEAS 1 FOOT
OR LESS.
SAT AND SAT NIGHT
E WINDS 5 TO 10 KT. SEAS 1 FOOT OR LESS,
THEN AROUND 2 FT. A CHANCE OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ235-211800-
RHODE ISLAND SOUND-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS AROUND 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: N 2 FT AT 3 SECONDS AND NW 2 FT AT
3 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING SW
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT. WAVE DETAIL: NE
2 FT AT 3 SECONDS AND NW 1 FOOT AT 3 SECONDS.
TUE NIGHT
SW WINDS 10 TO 15 KT. SEAS AROUND 2 FT. WAVE DETAIL:
SW 2 FT AT 3 SECONDS AND E 1 FOOT AT 3 SECONDS.
WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS 2 TO
3 FT. WAVE DETAIL: SW 3 FT AT 4 SECONDS AND SE 2 FT AT 4 SECONDS.
A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING E AFTER MIDNIGHT. SEAS
2 TO 3 FT. WAVE DETAIL: SE 3 FT AT 6 SECONDS AND W 1 FOOT AT
3 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: S 3 FT AT 7 SECONDS AND E 1 FOOT AT 4 SECONDS.
FRI AND FRI NIGHT
W WINDS 5 TO 10 KT, BECOMING SE. SEAS AROUND
2 FT.
SAT AND SAT NIGHT
E WINDS AROUND 10 KT. SEAS AROUND 2 FT. A
CHANCE OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ237-211800-
BLOCK ISLAND SOUND-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: N 2 FT AT 3 SECONDS AND NW 1 FOOT
AT 3 SECONDS.
TUE
NE WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING S
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT. WAVE DETAIL: NE
2 FT AT 3 SECONDS AND NW 1 FOOT AT 3 SECONDS.
TUE NIGHT
SW WINDS AROUND 10 KT. SEAS AROUND 2 FT. WAVE
DETAIL: SW 1 FOOT AT 3 SECONDS AND E 1 FOOT AT 4 SECONDS.
WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS 2 TO
3 FT. WAVE DETAIL: SW 2 FT AT 4 SECONDS AND SE 1 FOOT AT
3 SECONDS. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING NE AFTER MIDNIGHT.
SEAS 2 TO 3 FT. WAVE DETAIL: SE 3 FT AT 7 SECONDS AND W 1 FOOT AT
3 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: S 3 FT AT 7 SECONDS AND NE 1 FOOT AT 2 SECONDS.
FRI AND FRI NIGHT
W WINDS 5 TO 10 KT, BECOMING SE. SEAS AROUND
2 FT.
SAT AND SAT NIGHT
E WINDS 5 TO 10 KT. SEAS AROUND 2 FT. A
CHANCE OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ230-211800-
BOSTON HARBOR-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT. WAVES AROUND 2 FT.
TUE
N WINDS 5 TO 10 KT, BECOMING E IN THE AFTERNOON. WAVES
1 FOOT OR LESS.
TUE NIGHT
S WINDS 10 TO 15 KT. WAVES AROUND 2 FT IN THE
EVENING, THEN 1 FOOT OR LESS.
WED
S WINDS AROUND 10 KT. WAVES AROUND 2 FT.
WED NIGHT
S WINDS 5 TO 10 KT. WAVES 1 FOOT OR LESS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. WAVES 1 FOOT OR LESS.
FRI THROUGH SAT
NE WINDS 5 TO 10 KT. WAVES 1 FOOT OR LESS.
SAT NIGHT
SE WINDS 5 TO 10 KT. WAVES 1 FOOT OR LESS. A CHANCE
OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ236-211800-
NARRAGANSETT BAY-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS AROUND 10 KT. WAVES AROUND 2 FT.
TUE
N WINDS 5 TO 10 KT, BECOMING SW IN THE AFTERNOON. WAVES
AROUND 2 FT IN THE MORNING, THEN 1 FOOT OR LESS.
TUE NIGHT
S WINDS AROUND 10 KT. WAVES 1 FOOT OR LESS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
WAVES AROUND 2 FT. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING NE AFTER MIDNIGHT.
WAVES AROUND 2 FT.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. WAVES AROUND 2 FT.
FRI AND FRI NIGHT
NW WINDS 5 TO 10 KT, BECOMING SE. WAVES
AROUND 2 FT, THEN 1 FOOT OR LESS.
SAT AND SAT NIGHT
E WINDS 5 TO 10 KT. WAVES 1 FOOT OR LESS. A
CHANCE OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ280-211800-
OCEAN WATERS FROM THE MERRIMACK RIVER TO PLYMOUTH FROM 40 TO
60 NM-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS AROUND 15 KT WITH GUSTS UP TO 20 KT.
SEAS 3 TO 4 FT. WAVE DETAIL: N 3 FT AT 4 SECONDS AND E 2 FT AT
8 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING NE
5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N 3 FT
AT 5 SECONDS AND E 2 FT AT 8 SECONDS.
TUE NIGHT
S WINDS 5 TO 10 KT, INCREASING TO 10 TO 15 KT AFTER
MIDNIGHT. SEAS AROUND 2 FT. WAVE DETAIL: NE 2 FT AT 5 SECONDS AND
S 2 FT AT 5 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS 2 TO 3 FT. WAVE DETAIL: SW 2 FT AT 3 SECONDS AND NE 1 FOOT
AT 4 SECONDS.
WED NIGHT
S WINDS 10 TO 15 KT. SEAS AROUND 3 FT. WAVE DETAIL:
E 3 FT AT 4 SECONDS AND SW 2 FT AT 4 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: NW 2 FT AT 4 SECONDS AND SE 2 FT AT 5 SECONDS.
FRI THROUGH SAT NIGHT
SW WINDS 10 TO 15 KT. SEAS 2 TO 3 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ281-211800-
OCEAN WATERS FROM PROVINCETOWN TO NANTUCKET FROM 20 TO 60 NM-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 3 TO 4 FT. WAVE DETAIL: N 3 FT AT 4 SECONDS AND SW 2 FT AT
7 SECONDS. A CHANCE OF RAIN.
TUE
NE WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE MORNING.
SEAS 3 TO 4 FT. WAVE DETAIL: N 3 FT AT 5 SECONDS AND E 2 FT AT
8 SECONDS.
TUE NIGHT
E WINDS 5 TO 10 KT, BECOMING SW AFTER MIDNIGHT. SEAS
2 TO 3 FT. WAVE DETAIL: N 2 FT AT 5 SECONDS AND E 2 FT AT
8 SECONDS.
WED
S WINDS 5 TO 10 KT, INCREASING TO 10 TO 15 KT IN THE
AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: S 2 FT AT 4 SECONDS AND E
2 FT AT 6 SECONDS.
WED NIGHT
SE WINDS 5 TO 10 KT. SEAS 3 TO 4 FT. WAVE DETAIL: S
3 FT AT 4 SECONDS AND E 2 FT AT 9 SECONDS.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 3 TO 4 FT. WAVE
DETAIL: SW 3 FT AT 7 SECONDS AND NW 2 FT AT 3 SECONDS.
FRI THROUGH SAT NIGHT
E WINDS 10 TO 15 KT. SEAS 2 TO 4 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ282-211800-
OCEAN WATERS FROM MARTHAS VINEYARD TO NANTUCKET FROM 25 TO 60 NM-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 3 TO 4 FT. WAVE DETAIL: W 2 FT AT 5 SECONDS AND N 2 FT AT
6 SECONDS. A SLIGHT CHANCE OF RAIN.
TUE
NE WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE MORNING.
SEAS 2 TO 4 FT. WAVE DETAIL: N 3 FT AT 4 SECONDS AND W 2 FT AT
5 SECONDS.
TUE NIGHT
E WINDS 5 TO 10 KT, BECOMING S AFTER MIDNIGHT. SEAS
2 TO 3 FT. WAVE DETAIL: N 2 FT AT 5 SECONDS AND E 2 FT AT
8 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS 2 TO 4 FT. WAVE DETAIL: W 3 FT AT 5 SECONDS AND SE 3 FT AT
6 SECONDS. A CHANCE OF SHOWERS IN THE AFTERNOON.
WED NIGHT
SE WINDS 10 TO 15 KT, BECOMING E AFTER MIDNIGHT.
SEAS 4 TO 5 FT. WAVE DETAIL: S 3 FT AT 6 SECONDS AND E 3 FT AT
9 SECONDS. A CHANCE OF SHOWERS IN THE EVENING.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 3 TO 5 FT. WAVE
DETAIL: SW 4 FT AT 7 SECONDS AND E 3 FT AT 9 SECONDS.
FRI THROUGH SAT
NE WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
SAT NIGHT
E WINDS 10 TO 15 KT. SEAS 3 TO 4 FT. A CHANCE OF
SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ283-211800-
OCEAN WATERS FROM MONTAUK NY TO MARTHAS VINEYARD FROM 25 TO 60 NM-
105 AM EDT TUE APR 21 2026
REST OF TONIGHT
N WINDS 15 TO 20 KT. SEAS 3 TO 4 FT. WAVE
DETAIL: N 3 FT AT 4 SECONDS AND E 2 FT AT 8 SECONDS. A SLIGHT
CHANCE OF RAIN.
TUE
N WINDS 15 TO 20 KT, DIMINISHING TO 10 TO 15 KT IN THE
AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: NW 4 FT AT 5 SECONDS AND
E 2 FT AT 8 SECONDS.
TUE NIGHT
SW WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL:
N 2 FT AT 4 SECONDS AND SW 2 FT AT 5 SECONDS.
WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS 2 TO
4 FT. WAVE DETAIL: NW 4 FT AT 5 SECONDS AND S 3 FT AT 4 SECONDS.
A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 10 TO 15 KT, BECOMING E AFTER MIDNIGHT.
SEAS 4 TO 5 FT. WAVE DETAIL: SW 4 FT AT 6 SECONDS AND E 2 FT AT
9 SECONDS. A CHANCE OF SHOWERS IN THE EVENING.
THU AND THU NIGHT
NW WINDS 5 TO 10 KT. SEAS 3 TO 5 FT. WAVE
DETAIL: SW 4 FT AT 7 SECONDS AND NW 2 FT AT 4 SECONDS.
FRI AND FRI NIGHT
NW WINDS 10 TO 15 KT, BECOMING SE 5 TO
10 KT. SEAS 2 TO 3 FT.
SAT AND SAT NIGHT
E WINDS 10 TO 15 KT. SEAS 2 TO 4 FT. A
CHANCE OF SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/BOSTON
YOU CAN FOLLOW US ON FACEBOOK AT
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.BOSTON.GOV
YOU CAN FOLLOW US ON TWITTER AT
@NWSBOSTON
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page